Subcutaneous injection of methotrexate: Advantages in the treatment of rheumatoid arthritis.

Abstract

Methotrexate (MTX) is a conventional synthetic disease-modifying antirheumatic drug, which is used in the treatment of rheumatoid arthritis. However, insufficient responses to oral MTX at lower doses as well as increased variation of drug bioavailability and a deteriorated safety profile during dose escalation are regularly observed in patients. Some of its main side effects may be overcome by temporary drug hiatus or dose reduction or can be counterbalanced with folic acid. Especially gastrointestinal side effects are a major reason for permanent treatment discontinuation. Recent data suggest that MTX in a subcutaneous injection formulation can reduce gastrointestinal effects and thus may allow us to overcome oral intolerance and improve drug survival. Here, we review the currently available literature on the efficacy and safety of subcutaneous MTX in comparison to oral MTX in the treatment of patients with rheumatoid arthritis. Despite some inconsistency between data, an improvement in the efficacy and/or safety profile of subcutaneous MTX has been demonstrated. In the USA, subcutaneous MTX is an established second-line treatment already, while in European countries this formulation is even recommended as a first-line treatment. With the recent approval of subcutaneous MTX in Japan, another beneficial treatment option is now available for Japanese patients with rheumatoid arthritis.